Azo dyestuffs and their metal complex compounds



United States Patent Qfifice The present invention concerns azo dyestuifs of the general formula as well as their metal complex compounds.

In the general formula R denotes the radical of a diazo component wherein X is present in the -position relative to the azo bridge. A and B are hydrogen or substituents usual in azo dyestuffs which may be identical or difler from each other, for instance Cl, Br, nitro, acetylamino, methoxy, ethoxy, sulfonic acid, sulfonamide or sulfone groups; R is a lower alkyl, phenyl, CH COOH or a carboxylic acid lower alkyl ester group; and X represents a group capable of forming a complex, or an atom exchangeable for such a group, or a grouping which can be converted to a group of this type.

The novel metal-free dyestutfs of Formula I can be prepared by coupling suitable diazonium salts with pyrazolo [1,5-b][1,2,4]benzothiadiazine-dioxides[1,1] of the formula A H. 3 N\ r s 02 N at the 3-position of the pyrazole ring, wherein A, B and R have the above-specified significance.

Amines suitable for the preparation of the diazonium compounds are, for instance, 1-amino-2-hydroxybenzene, l amino 2 hydroxy 4 nitrobenzene, 1 amino2- hydroxy 4 chlorobenzene, 3 amino 4 hydroxybenzene-sulphonic acid-(1), 3 amino 4 hydroxy 5 chlorobenzene-sulphonic acid-( 1), 3 amino 4 hydroxybenzene-sulphonarnide-(l) and 4 amino 3 hydroxybenzene-sulphonamide-(l) and their derivatives substituted on the sulphonamide nitrogen atom by one or two organic radicals, ethyl (3-amino 4 hydroxyphenyl)- sulphone, amino-hydroquinone-methylene-sulphone ether, anthranilic acid, sulphoanthranilic acids,

anthranilic acid- 6 3,316,238 PaterrtedA p ZS, 1967 .2 sulphonamides as well as their derivatives substituted'on the amid nitrogen atom by organic radicals, also sulphanil; ic acid, 3-amino 4-methoxybenzene-sulphonamide-(1), 1 amino-2-chloro 5 nitrobenzene, 2-chloro-4-nitraniline, lamino-2-meth'oxy 4 nitrobenzene, 2-cyano-4-nitraniline, and 2,6di'chloro-4-nitnaniline. a i l Suitable pyraz'olo[1,5-b][l,2,4] benzothiadiazine dioxides[l,1] are, for example, Z-methyl-pyrazolo [LS-b] [1,2,4]benzothiadiazine-dioxide[1,1] 2,5,7 trimethylpyrazolo[l,5-b][l,2,4]benzothiadiazine dioxide[l','l]; 2,"Z dimethyl 6 chloropyrazolo[1,5-b][1,2,4]benzothiadiazine-dioxide[1,1]; 2 phenyl-pyrazolo[1,5-b] [1,2,4]benzothiadiazine-dioxide[1,1]; 2 methyl 7 nitro-pyrazolo [1,5-b] [1,2,4]benzothiadiazine. dioxide[1,1]; and methyl-pyrazolo[1,5-b] [1,2,4]benzothiadiazine dioxide [1,l]sulphonic acid-(7). The last of the listed coupling components is obtained by the sulphona'tion of 2-methylpyrazolo[l,5-b][l,2,4]benzothiadiazine-dioxide[l,l]. The above compounds may, for example, be prepared by cyclization of o-aminobenzenesulphopyrazolones of the general formula I SOs-N wherein R A and B have the above-indicated meaning in an acid medium to form pyrazolo[l,5-b] [1,2,4]benzothiadiazine dioxides[1,1] of the general Formula II.

In order to carry out the process for preparing the coupling compounds II the o-aminobenzenesulphopyrazolones are heated in water or organic solvents, such as methanol, ethanol, glycol monoethyl ether or formamide, dimethyl formamide or mixtures thereof, in the presence of organic or inorganic acids, such as aromatic sulphonic acids, hydrochloric or sulphuric acid. The reaction temperaturelies generally between about 30 C. and the boiling temperature of the reaction medium. The closed-ring compounds are subsequently separated by evaporating the solvent or by adding water.

According to a modification of the process it is also possible to transform o-aminobenzenesulphonic acid hydrazides directly into .the pyrazolobenzothiadiazine dioxides (II), for example with acetoacetic acid amide in an acid medium. v I i The metal complex compounds of these dyestufis are obtained by treating the azo dyestuffs of Formula I, in bulk or on a substrate, with metal discharging agents by a method known per se. For this purpose, dyestuffs of the givenformula, wherein X denotes a group capable of forming complexes or a grouping which can be converted to a group of this type, can be reacted with copper, chromium, cobalt, or nickel salts. If this reaction is carried out with copper salts in the presence of oxidising agents, it is also possible to employ those dyestuffs of the given formula wherein X denotes hydrogen; in that case, the hydrogen atom is exchanged for a hydroxyl group and this is simultaneously converted to the copper complex. By way of metallising compounds, it is also possible to employ those complex-forming compounds which already contain a chromium atom linked by a complex bond to a molecule and which are capable of forming a 'bond with another dyestufi molecule in order to form 2:1 complexes. This method produces mixed metal complex dyestuffs. Metallising is preferably carried out with the use of chromium discharging agents.

The dystuffs obtainable according to the process may have good, low, or no solubility in water, depending on the type of their substituents. The metal-free dyestuffs and those which are little soluble or insoluble are suitable for dyeing and printing synthetic materials such as polyesters and cellulose tri acetate. The metal complex compounds insoluble in water can be employed as pigments. The metal complex compounds soluble in water are particularly suitable for dyeing animal fibres; in addition, they can be fixed on cellulose fibres by chemical bonds in known manner if corresponding reactive groups are present.

The following examples are given for the purpose of illustrating the invention. The parts specified therein are parts by weight.

Example 1 dyestuff complex 18.8 parts of 1-amino-2-hydroxybenzene-4-sulphonic acid amide are dissolved in 75 parts of water and 30 parts of hydrochloric acid (d 1.19) and diazotised at C.

is separated by the addition of sodium chloride and then filtered off with suction. In order to prepare the chromium complex, the dyestufi is dissolved in 300 parts of water and 24 parts of sodium hydroxide solution (d 1.46) with heating, and after the addition of 70 parts of a solution of sodium chromoxalate which has a chromium content of 2.3% the solution is boiled under reflux for 3 hours. The chromium complex dyestuff which has thus'been formed is separated by the addition of sodium chloride, then filtered ofi? with 's'uction and dried. It consists of a dark powder, which dissolves in water with 'a viole-t colour and dyes wool from a weakly acidic bath to red-violet shades ofgood 'fastness properties, particularly with very good fastness to light.

Example 2 18.8 par-ts of 1-amino-2-hydroxybenzene-4-sulphonic acid amide are diazotised as described in Example 1. The diazonium salt solutionis then added at 05 C. to a solution of 24 parts of 2-methyl-pyrazolo[1,5-b][1,2,4] benzothiadiazinedioxide[1,1] in 400 parts of water and 25 parts of sodium hydroxide solution (d 1.46). When coupling has been completed, the resultant azo dyestuff of the formula is separated by the addition of sodium chloride and then filtered off with suction. For chroming, the dyestutf is dissolved in 300 parts of ethylene glycol. 17 parts of anhydrous sodium acetate are added, it is heated to 120 C., and then 13 parts of CrCl .6H O are gradually added. When chroming has been completed, the solution is added to 600 parts of water, the chromium complex is precipitated by the addition of sodium chloride and filtered off with suction. It consists of a dark powder, and dyes wool from an acidic bath to red-violet shades with good fastness properties.

The same complex is formed when the dyestutf solution obtained by coupling is heated to C. and treated during 30 minutes with a solution of 7.5 parts of potassium dichromate and 13.8 parts of glucose in 50 parts of water, whilst stirring thoroughly. After cooling, the 2:1 chromium complex is precipitated with sodium chloride.

For the preparation of the cobaltcomplex dyestufi, the solution of the monoazo dyestuif obtained by coupling is heated to 80 C. and treated with parts of the cohalt-containing solution which is described below. When dried, the cobalt complex dyestuff consists of adark brown powder, which dyes wool from an acidic bath to corinthbrown shades with good fastness properties.

The employed cobalt-containing solution was prepared by the following method: 500 parts of a 25% aqueous ammonium hydroxide solution were added to a solution of 281 parts of crystalline cobalt sulphate in 1000 parts of water with vigorous stirring; then air was blown in for a sufficiently long time for a sample no longer to produce a precipitate when 10% sodium hydroxide solution is added. The mixture was subsequently made up to 2000 parts with water.

By analogy with the description in Examples 1 and 2, the corresponding monoazo dyestutfs are prepared from the diazo amide including substituted lower alkyl and hydroxy lower alkylamides, the alkyl moieties thereof having a combined total of up to 2 carbon atoms, and coupling components listed in the following table, where their chromium complex compounds dye wool to the stated dye shades.

Example 3 22.3 parts of 1-amino-2-hydroxy-3-chlorobenzene-5- sulphonic acid are diazotised in the usual manner, and the diazotisation mixture is then addedt'o a solution'of 3 parts of 2 methyl pyrazolo[1,5-b][1,2,4]benzothiadidye shapes, with good fastness properties, after they have azine-dioxide[l,l]sulphonic acid-(7) in 300 parts of water subsequently been chromed.

Dye shade of dyeing Diazo component Coupling component on wool after subsequent chroming 4-chloro-2-an1inophenol-6-sulphonic acidn Bluish violet.

C 3 A l H 2-aminophenol-4-sulphon1c acid.-. 6H Bluish Bordeaux.

H N 2aminobenzoic ncid-5-sulphonic acid W CH Yellowish orange.

a a B H Z-emlnophenoM-sulphouic acid HO S OH Bluish red.

11 N 5-nitro-2-amiuophenol HO S CH Blulsh violet.

and 60 parts of sodium hydroxide solution (d 1.46) whilst Example 4 the temperature is maintained below C. by the addition of ice, When coupling has been completed, the result- 18 parts Of 2-cholo-4-n1tran1l1ne are triturated With 25 ant dy tufl f the f rmula parts of'hydrochloric acid (d 1.19), treated with ice, and diazotised with a solution of 7 parts of sodium nitrite Ho 01 in 20 parts of water. The solution is then added at 0-5 C. to a' solution of 24 parts of 2-methyl-pyrazolo[1,5-b] [1,2,4]benzothiadiazine-dioxide[1,1] in 600 parts of Water and 25 parts of sodium hydroxide solution (d 1.46). HO5S SOSH The dyestulf of the following constitution CH3 I N H is separated by the addition of sodium chloride and then filtered oif with suction. 1 CH3 Wool is dyed With this dyest-ufl? at 100 C. during 1 hour from an aqueous acidic bath to orange-red shades. \8/

Potassium dichromate solution is subsequently added to the dye bath and heating is continued for about 45 minutes. The dye shade of the dyeing on wool changes to bluish Bordeaux during this operation. The dyeing thus is precipitated by the addition of sodium chloride, filtered obtained exhibits good fastness properties. off with suction, and dried. It consists of a powder with By the same method, monoazo dyestuffs are obtained an orange colour, which dyes polyester materials and from the diazo and coupling components listed in the folcellulose triacetate orange shades.

lowing table, whose dyeings on wool produce the stated By the same method valuable dyestuffs are obtained from the. diazo and coupling components listed in the following table:

Diazo Coupling component Shade on component polyester NHa CH N Cl Reddisll yellow. CHs a S I 02 N NO:

NH2 on.

l Ol Orange.

S N i :4 NO;

ii W Q Do. a S

i 01 01- Do.

I CHa .N H3O Example 5 The coupling component used in Example 1 was prepared in accordance with the following prescription:

21 parts by volume of freshly distilled diketene are slowly added dropwiseto a mixture of 50 parts of phenol H and 0.5 part by volume of a sodium hydroxide solution maintaining the temperature at 4045 C. by immersing the reaction vessel into cold water. The mixture is finally cooled to 25 C., treated with 200 parts by volume of water and 2.5 parts by volume of acetic acid, and 53 parts of 3,5-dimethy1-2-aminobenzene sulphonic acid hydrazide are then introduced. An oily reaction mixture is formed which is stirred for 4 hours at 20 C. and one hour at C. After cooling, the water is decanted off, the oily layer dissolved in methanol and the o-aminobenZene-sulphopyrazolone is precipitated in crystalline form by the careful addition of Water. 67 parts of melting point 153- 154 C. are obtained.

.70. parts of this compound are heated to the boil for 30 minutes in 210 parts by volume of methanol and 210 parts by volume of semi-concentrated hydrochloric acid. After cooling, the reaction mixture is introduced into 1000 parts by volume of water, the precipitated crystals are filtered off with suction and re-crystallised from ethanol. 49 parts of 2,5,7-trimethyl-pyrazolo[1,5-b] [1,2,4]- benzothiadiazine dioxide [1,1] of melting point 265-267 C. are obtained. Results of analysis were as follows.

C H N O S (mol. wt. 263.15): Calculated, C, 54.75; H, 4.98; N, 15.96; 0, 12.15;. S, 12.15. Found, C, 55.07; H, 4.99; N, 16.02; 0, 12.31; S, 12.20.

Example 6 The coupling component used in Example 2 was prepared in accordance with the following method:

108.5 parts of Z-nitrobenzene-sulphonic acid hydrazide are stirred with 700 parts by volume of methanol and treated with parts by volume of acetoacetic acid ethyl ester. After a clear solution has been formed, 53 parts of anhydrous sodium carbonate are added and the mixture is then stirred at room temperature for another 12 hours in order to complete the ring closure. The sodium carbonate is then filtered off with suction, washed with methanol, the filtrate is made up to 1800 parts by volume with methanol and then hydrogenated at 3040 C. after the addition of Raney nickel at a hydrogen pressure of 20 atmospheres. After completion of the hydrogenation, the catalyst is filtered 01f with suction, the solvent concentrated in a vacuum, and the precipitated o-aminobenzenesulphopyrazolone (101 parts) is filtered off with suction.

To 64 parts of this compound, dissolved in 300 parts by volume of water, 50 parts by volume of concentrated hydrochloric acid are slowly added and the fine suspension is heated to CLfor 30 minutes. After cooling, the product is filtered off with suction and re-crystallised from ethanol. 48 parts of Z-methyl-pyrazolo[1,5-b]- [1,2,4]benzothiadiazine dioxide[1,1] are obtained of melting point -282283 C., with the following analytical results.

C1'6H9N3O2S (molecular weight 235.20): Calculated, C, 51.06; H, 3.86; N,17.87; O, 13.60; S, 13.60. Found, C, 50.96; H, 3.90; N, 17.73; 0, 13.74; S, 13.60.

Example 7 18.9 parts of 1-amino-2-hydroxybenzene-S-sulfonic acid are dissolved in partsof water and 30 parts of hydrorr soar;

monomethylamide.

1-amino-2-hydroxybenzene-sulfonie acid-(5)- Shade of the Diazo component Coupling component 015113121111; (gt-8111b H t N 1-amino-2-hydroxybenzene-sulfonie acid-(5)- hydroxyethylamlde. CH3 Redish violet.

S O: N l? l-amino-2-hydroxybenzene-sullonlc acid-(5)- Do.

morpho d. CHa

H N l-amino-Z-hydroxybenzenesulfonlc acid-(5)..-- T CHE-C O OCQHt Bordeaux.

N \S/ O: N

H Do i N Do.

' CONHa S O: N

N Do Bluish red.

CH: N 112N025 S 02 N E Do Brown.

CH.\1 N OSN \S/ \N H N Do Red.

CH: N I

0: OCH:

H Do H30 0 7 Do.

S O: N OH H N H038 NH: OH Red-brown.

E N HOaS S/ \N I 2 NH N do 01 l We claim: wherein A and B s 1. An azo dyestutf of the formula class consisting of hydrogen, x methoxy ethoxy, sulfonic aci N I I groups, R represents a member I A g Rx B N 70 sisting of lower alkyl,

lower alkoxy group, class consisting of s phenyl, nitro substit stituted phenyl, low

75 stituted phenyl and tand for radicals selected from the Cl, Br, nitro, acetylamino, sulfonamide and sulfone taken from the class conphenyl, --CH C0OI-I and a carbo R is a member selected from the ulfophenyl, chloro substituted sulfouted cyanophenyl, sulfonamide suber alkyl substituted sulfonamido subhydroxy lower alkyl substituted sul- -R stands for a diazo component from an o-amino-hydroxyphenyl sulfonic acid.

3. A dyestuff of claim 1 wherein X l R stands for a diazo component from a chloro substituted o-amino-hydroxyphenyl sulfonic acid.

4. The dyestufi of the formula 12 5. The dyestutf of the formula 6. The chromium complex of the dyestuif of claim 4. 7. The chromium complex of the dyestufi of claim 5. S. The cobalt complex of the dyestuif of claim 4. 9. The cobalt complex of the dyestuff of claim 5.

References Cited by the Examiner Derwent Belgium Patents Report, vol. 73A, page All, Feb. 3, 1961.

CHARLES B. PARKER, Primary Examiner.

IRVING MARCUS, Examiner.

REYNOLD FINNEGAN, DONALD M. PAPUGA,

Assistant Examiners. 

1. AN AZO DYESTUFF OF THE FORMULA 